This invention is generally directed to a punch press and in particular to a punch press for cutting windows in a ball cage.
In synchronized articulations for front wheel-drive cars, the engine torque is transferred by ball joints. These ball joints, usually six, are placed in a ball cage with regularly distributed windows. The windows are rectangularly shaped with very rounded corners. The two longitudinal planes of each window need to be carefully worked because the ball has to be guided axially with little play.
Conventional processing methods for making ball cages involves several steps. First, the blanks must be shaped. Next the inside and outside shapes are turned. The windows are next stamped and the longitudinal planes of the windows are broached. The cage is then case-hardened and the outside shape and longitudinal window planes are made smooth.
The broaching of the longitudinal planes of the window, necessary because of the broken surfaces resulting from the stamping, is an expensive processing step in the manufacturing of ball cages.
Accordingly, there is a need for a device which permits the precision cutting of windows in ball cages, in particular in combination with a triple effect fine blanking press, that obviates the need for the broaching step in the manufacture of ball cages.